我国历史上的私人秘书出现于()
A.部落联盟昌盛时期
B.夏
C.西周
D.春秋战国
参考答案:D
— What's wrong with her? Look at her ______ eyes.
— Yes, she must have been ______.
A.surprised; surprised
B.surprised; surprising
C.surprising; surprised
D.surprising; surprising
通风机安装工需要了解有关煤矿()的知识。
A、气体、煤尘爆炸
B、瓦斯、煤尘爆炸
C、瓦斯、粉尘爆炸
D、沼气、煤尘爆炸